1. Field of the Invention
The present invention relates generally to the art of fuel tank filler caps for motor vehicles including motorcycles, and more particularly to an insert for modifying conventional "quarter-turn" cap retainers. In its preferred embodiment, the present invention relates to an insert assembly for a conventional fuel filler cap retainer in which the insert assembly is used to modify the retainer for receipt of a removable filler cap of the threaded type.
2. Description of the Prior Art
In recent years, there has been a tendency to utilize threaded fuel tank filler caps for automobiles and other passenger car and truck applications, and in marine, industrial and similiar applications. These caps include a molded plastic, externally threaded, hollow stem received by the mating threads of a filler cap retainer made especially for cooperation with the threaded filler cap. Prior fuel tank filler caps generally provided a filler cap retainer with diametrically opposed notched areas leading into a cam surface declining inwardly of the central opening. The opening was adapted to receive cooperating locking cam follower portions on the filler cap when rotated one-quarter turn, to provide a removable closure for a fuel tank. The sealing surface of the former cap retainers was necessarily kept to a minimum and was often abraded, dented or otherwise deleteriously affected by rough handling of a gas or diesel oil supply nozzle. This has been especially true since the advent of the "self-service" stations where untrained automobile and motorcycle operators personally dispense fuel in the tanks of their motor vehicles.
With these deficiencies in mind, the present invention contemplates the use of an insert assembly to be inserted and permanently held in place within the confines of the conventional diametrically oppositely disposed notched areas of a cap retainer. This insert is further arranged with threading adapted to receive the threaded portion of a fuel tank filler cap.